It is known that the bottoms of steelworks converters provided with blast tuyeres are very expensive. Consequently steel specialists have given considerable attention to increasing the service life of these bottoms as much as possible. The service life not only depends on the wear of the lining constituting the bottom, but also on the wear of the blast tuyeres. The present invention therefore relates to a tuyere whose particular construction ensures an extended service life with respect to the average at present obtained.
The invention is based on the following considerations. During numerous tests with tuyeres comprising a cylindrical tube into which at least one refining fluid is introduced by means of a convergent duct located at one end of this tube, the other end communicating with the converter, we observed that the tuyeres exhibited wear due to abrasion localised in a short zone of the tube. In order to reduce this wear, it is necessary to protect this zone by means of an abrasion resistant material and, in particular, a material which is resistant to abrasion by lime suspended in the blast. We also observed that the length of the zone exhibiting wear was dependent on the shape of the convergent duct. Furthermore, it is advantageous to limit the length of the tube to be protected to a minimum, as the cooling of the tuyere by the passage of the fluid is one of the factors contributing to the effective resistance of the tuyere.